1. Field of the Invention
The present invention relates to micro aspherical lenses and a fabricating method therefor, and optical fiber coupling devices, focusing optical systems, optical devices, semiconductor laser light sources and image devices utilizing the micro aspherical lenses as well as multi-beam projectors.
2. Description of the Background Art
Micro lenses have the advantage of compactness and light weight. Micro lenses heretofore known include (a) a ball lens, (b) an ion exchange flat micro lens, and (c) a Fresnel lens. In addition, aspherical lenses have the advantage of causing no aberration. Aspherical lenses heretofore known include, for example, (d) an aspherical plastic lens used in an optical pick-up of an optical disk. However, the lenses have various disadvantages as described in following.